diff --git a/faa_osc/faa_osc.ino b/faa_osc/faa_osc.ino
index b9ad1cd..7f99757 100644
--- a/faa_osc/faa_osc.ino
+++ b/faa_osc/faa_osc.ino
@@ -26,6 +26,18 @@
 #define WIFI_CHANNEL 1
 //============</parameters>===========
 
+//============<configurations>============
+//
+// MONITORING_ACTIVE
+// : activate serial communication monitoring @ TX1, if defined.
+//   since 'Serial' is occupied by 'SLIPSerial',
+//   alternativly 'Serial1' will send out messages.
+//
+//   'Serial1' - D4/GPIO2/TDX1 @ nodemcu (this is TX only.)
+//
+//============</configurations>============
+// #define MONITORING_ACTIVE
+
 //arduino
 #include <Arduino.h>
 
@@ -96,8 +108,10 @@ void route_note(OSCMessage& msg, int offset) {
         //
         esp_now_send(NULL, frm, frm_size); // to all peers in the list.
         //
-        Serial.write(frm, frm_size);
-        Serial.println(" ==(esp_now_send/0)==> ");
+#if defined(MONITORING_ACTIVE)
+        Serial1.write(frm, frm_size);
+        Serial1.println(" ==(esp_now_send/0)==> ");
+#endif
         //
     }
 }
@@ -159,15 +173,18 @@ Task blink_task(0, TASK_FOREVER, &blink, &runner, true); // -> ENABLED, at start
 // on 'receive'
 void onDataReceive(uint8_t * mac, uint8_t *incomingData, uint8_t len) {
 
-    //
-    Serial.write(incomingData, len);
+#if defined(MONITORING_ACTIVE)
+    Serial1.write(incomingData, len);
+#endif
 
     // open => identify => use.
     if (incomingData[0] == '{' && incomingData[len - 1] == '}' && len == (sizeof(Hello) + 2)) {
         Hello hello("");
         memcpy((uint8_t *) &hello, incomingData + 1, sizeof(Hello));
         //
-        Serial.println(hello.to_string());
+#if defined(MONITORING_ACTIVE)
+        Serial1.println(hello.to_string());
+#endif
         //
         OSCMessage osc("/hello");
         osc.add(hello.id);
@@ -188,7 +205,9 @@ void onDataReceive(uint8_t * mac, uint8_t *incomingData, uint8_t len) {
         Note note;
         memcpy((uint8_t *) &note, incomingData + 1, sizeof(Note));
         //
-        Serial.println(note.to_string());
+#if defined(MONITORING_ACTIVE)
+        Serial1.println(note.to_string());
+#endif
     }
 }
 
@@ -249,6 +268,11 @@ void setup() {
     // start SLIPSerial on Serial
     SLIPSerial.begin(57600);
 
+    // start Serial1 as an alternative
+#if defined(MONITORING_ACTIVE)
+    Serial1.begin(115200);
+#endif
+
     // clear out any leftover debris. (this will let LED blinking works from initialization.)
     while(SLIPSerial.available() > 0) {
         SLIPSerial.read();